Cytotype Regulation by Telomeric P Elements in Drosophila melanogaster: Interactions with P Elements from M's Strains
Michael J Simmons 1*, Jarad B Niemi 1, Don-Felix Ryzek 1, Cecile Lamour 1, Joseph W Goodman 1, Wojciech Kraszkiewicz 1 and Ryan Wolff 1
1 University of Minnesota, Twin Cities
* To whom correspondence should be addressed. E-mail: simmo004{at}umn.edu.
Submitted on October 11, 2006
Revised on February 13, 2007
Accepted on 21 May 2007
 |
Abstract |
|---|
P strains of Drosophila are distinguished from M strains by having P elements in their genomes and also by having the P cytotype, a maternally inherited condition that strongly represses P-element-induced hybrid dysgenesis. The P cytotype is associated with P elements inserted near the left telomere of the X chromosome. Repression by the telomeric P elements TP5 and TP6 is significantly enhanced when these elements are crossed into M's strains, which like P strains carry P elements, but have little or no ability to repress dysgenesis. The telomeric and M's P elements must coexist in females for this enhanced repression ability to develop. However, once established, it is transmitted maternally to the immediate offspring independently of the telomeric P elements themselves. Females that carry a telomeric P element but that do not carry M's P elements may also transmit an ability to repress dysgenesis to their offspring independently of the telomeric P element. Cytotype regulation therefore involves a maternally transmissible product of telomeric P elements that can interact synergistically with products from paternally inherited M's P elements. This synergism between TP and M's P elements also appears to persist for at least one generation after the TP has been removed from the genotype.
Key Words:
P elements, cytotype, hybrid dysgenesis, telomere, transposon
